Anne Frank, April 1941: a new study claims her diary was intended as a work of art. Photograph: AP

In a brilliant observation, Philip Roth once described Anne Frank as Kafka's "lost little daughter". Frank's diary of her sequestration in the secret annexe of 263 Prinsengracht in Amsterdam is surely one of the most compelling documents of 20th-century European history, a heartbreaking, at times uplifting, record of a young life scorched and then exterminated by the Nazis.

But the title is misleading. Yes, it was first a diary, a teenage girl's response to extraordinary and terrifying day-to-day events. On closer examination, however, the back story of the "diary" and its composition reveals neither a wordstruck ingenue nor an impetuous adolescent scribbler but a precocious young writer at pains to create a work of art. Such is the argument of an absorbing new study by the American critic Francine Prose – Anne Frank: The Book, the Life, the Afterlife (Atlantic £16.99, pp336).

Prose explores how the book that began as Het Achterhuis ("the house behind") went through many drafts in composition, and then several postwar incarnations before it acquired its canonical title, The Diary of Anne Frank – as a Broadway play. Prose also describes how Frank discovered her vocation as a writer through the experience of confiding her thoughts to a cardboard-bound notebook, and how the text she created has become a touchstone of 21st-century responses to the atrocities of Nazism.

It is a measure of Frank's achievement that her work has inspired the most partisan and obsessive devotion on Broadway and in Hollywood, as well as provoking some of the most ludicrous episodes in the vile catalogue of Holocaust denial. Among those people, it has become commonplace to claim that The Diary of Anne Frank is a forgery.

The afterlife of books is one of the mysteries and fascinations of any library. Very many books, especially in this age of overproduction, are little better than Hello! magazine and leave virtually no trace in the sand. There are, however, three kinds of title that linger in the mind, and Anne Frank's diary has something of each.

First, there are what you might call the sacred texts of western civilisation, constantly reread and reinterpreted: for instance, the Bible, the works of Shakespeare, Cervantes and Milton, the novels of Franz Kafka. These are all classics, though not all classics enjoy the same afterlife. Utopia is a classic, but for every 100 people who cheerfully use the word "utopian", only a handful will be familiar with Thomas More's text.

Second, there are what I will call "zeitgeist books", volumes of fiction, poetry or ideas whose original appeal is inextricably linked to a moment in history. For instance, Penguin Modern Classics has just reissued John Le Carré's The Spy Who Came in from the Cold, a cold-war thriller that, 50 years on, speaks to a new generation of readers, describing a world now almost as remote as Edwardian England. Aldous Huxley's Brave New World is another zeitgeist book whose afterlife transcends its year of publication (1932). In our own time, Naomi Klein's No Logo is another zeitgeist book perhaps still too current to have acquired an afterlife.

And then, finally, there is that shelf in the library of European masterpieces whose authors, as Francine Prose puts it, "have been forced into a collaboration with misfortune", books that were made at an unendurably high cost to the writer. Nadezhda Mandelstam's memoir of Stalin's terror, Hope Against Hope, is one of these, and so are the works of Primo Levi.

As Prose admits, the terrible circumstances of composition must colour our understanding of how good these books actually are, and to what extent they are works of art. But, as she says of Anne Frank, her "unique and beautiful voice is still being heard by readers who may someday be called upon to decide between cruelty and compassion". If, as a result, a government official in Kazakhstan or a secret policeman in Latin America "opts for humanity and chooses life over death", that will be the vindication of a diary, written in an attic, by a 13-year-old Dutch girl in the 1940s.

First came the book, now comes the saga...

Afghanistan was in the courts last week, and not a mention of Wikileaks. The grinding wheels of Scandinavian justice handed down a verdict against the Norwegian journalist Åsne Seierstad, who published
The Bookseller of Kabul as long ago as 2003, provoking the righteous indignation of the eponymous Afghan bookseller Shah Muhammad Rais. The bookseller and his family launched an opportunistic international campaign to discredit her and, more profitably, to extract remuneration from the author in recompense for the alleged violation of the family's privacy, despite his wholehearted support of the book. Seierstad stoutly resisted these efforts, but last week an Oslo court ruled that she was "negligent" and should pay 250,000 kroner to Suraia Rais. I am delighted to see that Ms Seierstad and her publisher will be appealing this questionable verdict.

You set me up... and I'll knock you down

Kit and the Widow (Kit Hesketh-Harvey and Richard Sisson) have been trading saucy double entendres at country house parties for about 30 years with (apparently) never a cross word. But this hallowed partnership may be about to come under some temporary strain. Sisson is publishing
The Widow's Tale with Constable this autumn, just six months before Hesketh-Harvey's own scandalous memoirs hit the bookshops. Mischievous observers are said to be hoping for some kind of hissy fit when the pair shortly make their annual appearance at the Edinburgh festival fringe.